Portable Water Filters for Travelers & Hikers
People travel for many reasons - for education, curiosity, to help others, to have adventures, and to some places to get healthier. Any type of travel is likely to be ruined, though, if contaminated water leads to intestinal problems, as happens with 20-50% of travellers per year (Wikipedia). You can prevent that possibility by packing a portable water filter of some kind.
Knowing where you're going and what the water situation is like there will help, and there are many ways to find out: Ask people who've been there. Ask people you know there. Ask your travel agent. Ask other travelers online.
Drinking Water Contamination
The U.S. Environmental Protection Agency reports that 90 percent of the world's water is contaminated in some way. The World Health Organization (WHO) attributes 80 percent of all travel diseases to contaminated drinking water. This means that even in the backcountry of one's own nation, it's important to clean the water you drink.
Because clean water means more than just the lack of dirt or leaves, safety procedures also need to consist of more than just a visual inspection. To combat the intestinal diseases so often acquired by sensitive travelers, the U.S. military and subsequent manufacturers have developed a number of different types of portable water treatments.
Water Filter vs. Water Purifier
There is a distinct difference between filtration and purification. With filtration you are passing water through a screen of a certain size that blocks anything bigger than its holes from passing through. This includes bacteria, viruses, and protozoa that might otherwise cause disease. It will also take out any flotsam, of course (leaves, twigs, etc). The size of the holes is a key factor, depending on where you are traveling and the organisms most prevalent in the water there.
With water purification, on the other hand, treatment focuses on chemical or mechanical alteration of the organisms' life functions, including blocking their ability to reproduce. Most microorganisms need to be present en masse, in order to create problems in the human body. Rapid reproduction is therefore a key survival function for them. Block their reproductive ability and you effectively block the disease.
Portable Water Treatment Systems
The easiest way to treat water when on the go - assuming you have access to a source of heat - is to boil or pasteurize it to eliminate microbes. Hikers and campers usually take a pan or teapot with them anyway. This is all most hardy travelers need, unless the place they are going to is particularly disease-ridden. The average traveler, however, needs a little more protection than boiling, both for drinking and also brushing teeth.
The kind of protection you choose will depend on the hardiness of your physical constitution and on what kind of water will be available where you go, and its size will depend on the type/s of vehicle/s in which you plan to travel and the amount of luggage you will be taking. The description of the following treatments reflects the technology, not the brand, however the brand does give you an idea of potential cost.
Water Purification Tablets or Drops - In the 1940s the US Army commissioned Harvard University to find a simple purification method for use in the field. Harvard developed iodine tablets or drops to use for emergencies. Now they are used by travelers as well.
Iodine drops temporarily protect one against giardia lamblia, which is the water-borne microorganism most commonly associated with diarrhea. The iodine in the tablet penetrates the organisms' cell walls, rendering them inactive and the water semi-safe to drink within 30 minutes.
The iodine leaves a bit of a weird taste, which adding Vitamin C tablets after the treatment helps improve. Both make a good addition to a standard first aid kit. Note that an opened bottled of iodide tablets loses its effectiveness after 3 months. List price is $5.95.
Water Filter Gravity Bag - Designed especially for backpacking, this is a waterproof, lightweight vinyl bag that rolls up for convenience. Inside it has ceramic/carbon filters impregnated with silver to kill bacteria like ecoli, cryptosporium, and giardia. The filter size is 0.3 to 0.7 microns, depending on the make. The larger size will not filter out viruses. The carbon inside removes odors and weird tastes, leaving the water clear and tasting good.
Filtration takes place in about 15 minutes, using the pull of gravity. Water is poured into the top of the bag, which is hung from a branch, and comes out the bottom through a hose. Easy to use for camping. Can weigh as little as 14 ounces, depending on the brand. Capacity is 2.5 gallons per fill. Can filter 50-150 gallons before inside filters need replacing. Approximate list price: $80.
This type of filter can be used by international travelers, as well as hikers. It uses a ceramic/silver core and the filtration size is 0.2 microns, smaller than the gravity bag. Rather than pouring water into it, it has a pump and a hose to attach to water containers. Prices have dropped dramatically in the last few years and sizes have diminished as well, so they are very affordable. The filters can be washed and reused. They weigh around 20 ounces. Capacity is about 20,000 gallons.
UV Water Purifier
The Steripen UV Water Purifier won the Backpacker Editors Choice award in 2011. Rather than purifying using chemicals, it purifies using ultra-violet light, destroying 99.99% bacteria, protozoa, and even viruses. The UV lamp turns on automatically when the "pen" is placed in water and can be used over 8,000 times. Uses two non-rechargeable lithium batteries. This type of UV purification is used by water suppliers and bottling companies. The Steripen may not be shippable to international destinations, due to lithium batteries.
Best Water Treatment System
The best treatment system for you and your trip is going to vary, depending on a number of factors:
- Your intestinal stamina
- Your luggage capacity
- How often you will need to treat water
- Water availability and quality in the places you go
- Length of time you usually spend there
- Availability of modern conveniences
- Size of your budget
Water Treatment Technologies Compared
The Ultimate Choice
You may be wondering why boiling water is not enough. It usually is . . . in locations where a stove or firewood are available. Many countries are conserving firewood, though, or don't have any, or you may be hiking to an alpine mountaintop. In other areas fire hazard is a problem. In populated areas you may be staying in small hotel rooms or hostels where stoves are not available. A portable filter or purifier is a good idea to take with you wherever you go.
Alkaline Water Purifier
This is a purifier containing an alkaline and magnet core that re-mineralizes tap water. It also filters out bacteria and protozoa, and removes chlorine, insecticides, and heavy metals. It produces ionized water that is a better antioxidant than vitamin C and helps increase both oxygen and energy levels. As a longtime health nut, I believe this technology to be the healthiest, since it changes the base of the water from acid to alkaline. Most disease-producing microbes cannot live in an alkaline environment. Over 1,300 refills per filter. 20 ounce capacity per fill. Weight 350 grams (13 ounces).